Brussels-Capital Region: localization of the discharge points of the two treatment stations of wastewater and rainwater of the Brussels agglomeration.

Brussels-Capital Region: localization of the two treatment stations of wastewater and rainwater. The Brussels-North waste water treatment plant (AQUIRIS commissioned in 2007) and the waste water treatment plant Brussels-South (commissioned in 2000).

Brussels-Capital Region: Delineation of the Brussels agglomeration, in accordance with the directive 91/271/EEC concerning urban waste water treatment. The agglomeration is there defined as "an area where the population and/or economic activities are sufficiently concentrated for urban waste water to be collected and conducted to an urban waste water treatment plant or to a final discharge point". It corresponds to the two collecting basins of the waste water treatment plants of Brussels-North and Brussels-South.

Brussels-Capital Region: The sensitive area to eutrophication is a protected area against the pollution of surface waters caused by waste water. This area matches the Senne river basin. In this area, urban waste water has to be collected and are subject to a stringent treatment before their discharge. It was designated in accordance with the prescriptions of the European Directive 91/271/EEC, by the Regional Decree of 23 March 1994.